Vacuum-pump.



H. D. MADDEN.

VACUUM PUMP.

APPLICATION FILED 00T.8, 1910.

1,031,801 Patented July 9,1912.

2 SHEETS-SHEET 1.

WITNESSES: INVENTOR H. D. MADDEN.

VACUUM PUMP.

APPLICATION FILED 00T.B, 1910.

1,031,801. Patentd July 9, 1912.

2 SHEETS-SHEET 2.

WITNESSES: INVENTOR QMV (2/40 6. Ci /L4 ATTORNEY HARRY D. MADDEN, BLOOMFIELD, NEW JERSEY, ASSIGNOR TO WESTINGHOUSE LAMP OOMPANY, A CORPORATION OF PENNSYLVANIA.

VACUUM-PUMP.

Specification of Letters Patent.

Application filed October 8, 1910i Serial No. 586,082.

To all whom it may concern Be it known that I, HARRY D. MADDEN, a citizen of the United States, and a resident of Bloomfield, in the county of Essex and State of New Jersey, have invented a new and useful Improvement in Vacuum-Pumps, of which the following is a specification.

My invention relates to vacuum pumps and particularly to discharge devices or valyes therefor.

The object of my invention is to provide a dischargedevice for vacuum pumps that shall have nomovable parts, and shall be effective to prevent the gas being pumped from returning into the pump chamber.

Figure 1 of the accompanying drawings is a side and sectional view of a pump that embodies my invention, and Fig. 2 is an end and sectional view of said pump. The pump to which the present invention is applied comprises a stationary'member 1 that is mounted within a casing 2 and is provided, at one end, with a cylindrical chamber? The-stationary member is also provided with an inlet port 4 leading to one side of the cylindrical chamber '3 from a pipe 5, that is connected tothe chamber to be exhausted, and with an exhaust port 6 leading from the top of the cylindrical chamber 3 to a partially oil-filled chamber 8 provided by a member Qthat is mounted upon the stationary member 1 and in wh1ch an auxiliary Vacuum is maintained.

Rotatably mounted in the stationary member 1, and adapted to be drivenby a pulley '10, is a member 11 having a cylindrical enlargement upon its inner end, that is located within, and is mounted eccentrically with respect to, the cylindrical chamber 3 and bears against one side thereof. The enlarged end of the rotatable member 11 is provided with diametrically. opposite slots in which operate two plates or valve mem-. bers 12, that are normally pressed outwardly against the wallsof the cylindrical chamber 3 by means-of a spring 13. It will be understood that, as the member 11 rotates, the plates 12 are moved inwardly and outwardly, and air is taken in through the pipe 5 and the inlet port 4 and is discharged into the chamber 8 through the exhaust port 6, the chamber 3 being filled with oil, and the air being discharged in the form of bubbles in the oil.

The parts which have thus far been described are old in the art and constitute no part of the present invention, which will now be described.

Mounted upon the stationary member 1, over the exhaust port 6, is an inverted which are closed and at the base of which passages 15 are provided for afiording comexhaust port 6. The inverted trough or V- shaped member 14 is provided, at or near its apex, with an opening or slit 16 that is narrow and of small-cross-sectional area as compared vwith the passages 15. Oil containing bubbles of air or gas is forcibly discharged by the movable pump parts into the member 14, and from there, through the passages 15 and the slit 16 into the chamber 8. As the air bubbles tend to rise in the oil, they are discharged principally through the slit 16, the force of the discharge being increased by the .tapering of the member 14, and they arethereafter prevented from rentering the member 14 through the slit because of its narrowness. Clear oil returns: to the pump chamber through the passages 15 at the base of the member 14, these passages being considerably-below the surface of the oil where the bubbles collect and burst. As heretofore constructed, such valves have been provided with movable members that are raised to permit of the passage of bubbles therethrough and are closed upon the occurrence of tendency for the bubbles to return therethrough. Consequently, energy is lost in operating the valve and it is impossible to produce as good a vacuum therewith as with the valve of the present invention. I

I claim as my invention: 1. In a vacuum pump, with a stationary member having inlet and discharge ports, and a rotatable member cooperating therewith, of an inverted V- shaped shell over the discharge port in the narrow slit in its-apex.

2. In a vacuum pump, "the combinatlon with a stationary memberhaving inlet and discharge ports, and a rota-table member cooperating therewith, of an inverted V- shaped shell over the discharge port 1n the stationary member, the said shell havmg a Patented J uly9, 1912.

trough or V-shaped member 14, the ends of munication between the chamber 8 and the the combination narrow slit in its apex and a passage communicating with the discharge port at the baseof the-shell.

8. In a vacuum pump, the combination with a stationary member having inlet and discharge ports, and a rotatable member cooperating therewith, of an internally tapered shell over the discharge port in the stationary member, the said shell having an outlet passage at its apex that is narrow as compared With the dimensions of the dis charge port. v

4. In a vacuum pump, the combination with 'a stationary member having a discharge port, of an internally tapered shell over the discharge port having a discharge opening in'its upper narrower portion that is narrow as compared with the dimensions of the discharge port, a large opening relative to the said discharge opening being provided at the base of the said shell.

5. In a vacuum pum the combination with a stationary mem er having a distember, 1910.

charge port, of an internally tapered shell over the discharge port having a discharge opening in its upper narrower portion that is narrow as compared with the dimensions of the discharge port.

6. In a vacuum pump, the combination with a member having a discharge port, of an internally tapered member over the slit port having a discharge in its upper narrower portion that is narrow relatively to the discharge port.

7. A vacuum pump comprising a member having a discharge port,-and a member having a dischargeopening in its upper portion that is narrow as compared with the di I mensions of thedischarge port.

In testimony whereof, I have hereunto subscribed my name this 26th day of Sep- HARRY D. MADDEN; Witnesses:

W. O. HIPPLE, 'B. W. OGDEN. 

